Can we create reference of abstract class in C++?

You can’t create an object of an abstract class type. However, you can use pointers and references to abstract class types. You create an abstract class by declaring at least one pure virtual member function. That’s a virtual function declared by using the pure specifier ( = 0 ) syntax.

Can you have a reference to an abstract class?

A reference to an abstract class is just like a pointer to an abstract class: it needs to reference an object of some non-abstract subclass of the abstract class. You can use a reference like that to call virtual methods on the referenced class using the . syntax, in a way similar to a pointer to an interface in Java.

What is an abstract class CPP?

An abstract class is a class that is designed to be specifically used as a base class. An abstract class contains at least one pure virtual function. You declare a pure virtual function by using a pure specifier ( = 0 ) in the declaration of a virtual member function in the class declaration.

What is use of abstract class in CPP?

Abstract classes are used to express broad concepts from which more concrete classes can be derived. An abstract class type object cannot be created. To abstract class types, however, you can use pointers and references. Declare at least one pure virtual member feature when creating an abstract class.

Can we have reference to interface?

Yes, you can. If you implement an interface and provide body to its methods from a class. You can hold object of the that class using the reference variable of the interface i.e. cast an object reference to an interface reference.

Do you have to override abstract methods C++?

If you don’t want it abstract, you have to remove the =0 . However, once you do that, you can’t force the derived classes to provide their own implementations. In other words, you have to make a choice.

What is difference between abstract class and interface in C++?

An “interface” embodies the concept of a contract between clients and an implementation. An “abstract class” contains code that you want to share between multiple implementations of an interface. While the interface is implied in an abstract classes methods, sometimes it is useful to specify the contract in isolation.

Can an interface reference a class?

Can you overload an abstract method?

We cannot create objects of an abstract class. To implement features of an abstract class, we inherit subclasses from it and create objects of the subclass. A subclass must override all abstract methods of an abstract class. However, if the subclass is declared abstract, it’s not mandatory to override abstract methods.

Which is faster interface or abstract class?

The performance of an abstract class is fast. The performance of interface is slow because it requires time to search actual method in the corresponding class. It is used to implement the core identity of class.

Can abstract class have main () function defined inside it?

Can abstract class have main() function defined inside it? Explanation: This is a property of abstract class. It can define main() function inside it. There is no restriction on its definition and implementation.

Why are there no interfaces in C++?

An interface isn’t simply a class whose methods are all abstract. It is a distinct kind of type which has no precise analogue in C++ because the language constraints which enable it to exist don’t apply in C++. Namely, C++ has multiple inheritance.